SU1577784A1 - Device for controlling motor apparatus - Google Patents

Abstract

The invention relates to medicine and can be, in particular, used in the construction of walking machines and in prosthetics. The purpose of the invention is to improve the accuracy of controlling the coordinated movements of the apparatus. The control unit of the motor apparatus contains a sensor 1, a first standby multivibrator 2, a first differentiating circuit with a limiter 3, a second standby multivibrator 4, a first emitter follower 5, a sawtooth voltage generator 6, a third standby multivibrator 7, the first amplifier 8, a second differentiating circuit with a limiter 9, an integrating chain 10, a second amplifier 11, a second emitter follower 12, a pulse amplifier 13, a second-order link 14, a power amplifier 15, an integrator 16 and an actuator with electro drive 17 and foot 18. The device can be used to control the flexion of the foot during prosthetics, as well as when designing an artificial foot of walking devices. 3 il.

Description

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The invention relates to medicine and can be, in particular, used in the construction of walking machines and in prosthetics.

The purpose of the invention is to improve the accuracy of controlling the coordinated movements of the apparatus.

FIG. 1 shows a block diagram of a control device; in fig. 2 - pulse forms formed by individual units of the device; in fig. 3 - amplitude characteristics of the integrator.

The control unit contains sensor 1, the first standby multivibrator 2, the first differentiating circuit with limiter 3, the second standby multivibrator 4, the first emitter follower 5, the sawtooth voltage generator 6, the third standby multivibrator 7, the first amplifier 8, the second differentiating circuit with limiter 9, integrating chain 10, second amplifier 11, second emitter follower 12, pulse amplifier 13, second-order link with amplifier 14, power amplifier 15, integrator 16 in the form of a proportional-integrating link and an actuator with an electric actuator 17 that drives the foot 18. The sensor 1 is made up of a magnet, which is mounted on the inner side of one leg, and a coil mounted against the magnet on the other leg. Inside the coil is a core of magnetic material. Structural elements of sensor 1 in the drawings are not listed.

The control unit of the motor apparatus operates as follows.

When the left leg is moving forward, a miniature magnet passes in the immediate vicinity of the coil and induces an emf in the form of a triangular pulse 19 in its winding. When moving the right leg forward, a similar emf is induced, but in negative polarity. Only a pulse of positive polarity triggers the first standby multivibrator 2, generating a rectangular pulse 20. A differentiating circuit with limiter 3 differentiates this pulse into two pointed pulses 21, limits the positive pulse and transmits only a pulse 22 of negative polarity. This pulse triggers the second pending multivibrator 4, which generates a pulse 23 delayed by time T relative to pulse 19 to delay the start of flexion of the foot. The passage of the first emitter follower 5, the pulse 23 is supplied to the sawtooth generator 6 as a supply voltage. The pulse duration 24 of the sawtooth voltage is equal to the pulse duration 23. The pulse 24 is used as the trigger voltage of the third

a standby multivibrator 7, generating frequency-modulated pulses 25. Simultaneously, the pulse 24 of the sawtooth 6 generator 6, through the second amplifier 11 and the second emitter follower

12 is supplied as supply voltage to the first amplifier 8, from which output amplitude-frequency-width-modulated pulses 26 are removed. These pulses pass through a differentiating chain with limiter 9, which is from amplitude-frequency-width-modulated pulses 26 or shown separately the initial pulses 27 of the first amplifier 8 generates triangular pulses 28, the duration of which is proportional to the amplitude. Pulses 28 after passing through the integrating chain 10 are converted into pulses 29, which are fed to the pulse amplifier 13. Signals in the form of pulses with amplitude-frequency-frequency-modulated modulation-26 are sent to the input of the pulse amplifier 13. From the output of the pulse amplifier 13, the signals enter the channel negative feedback formed by the link of the second

5 order 14 in the form of a series-connected peak detector, an integrating chain and an adjustable shunt (not labeled). The time constants of the negative feedback channel links are chosen such that, under the action of a single pulse, the device generates an exponential voltage for 20 ms and then extinguishing to 300 ms. From the output of the block

The 13 pulse signals are passed through the power amplifier 15 and are fed to the integrator 16, made in the form of successively connected peak detector and a proportional-integrating element (not indicated). At the integrator, the pulses are summed and the discrete signals are converted to analog. Voltage

Q on the integrator 16 depends on the amplitude, frequency and duration of the incoming pulses. If at the end of the period of the control discrete signal 26 the voltage, frequency and duration of the pulses have a maximum voltage, and at the beginning of the period, respectively, the minimum voltage, the signal on the integrator 16 will correspond exactly to the modulating signal. Therefore, the voltage across the integrator 16 will increase according to the sawtooth law. Therefore, the signal on integrator 16 will correspond exactly to the control signal. The triple mode of modulation ensures the linearity of the amplitude characteristic shown in graph 30. This is due to the fact that if the input of the pulse amplifier 13 were received

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only the frequency-modulated pulses are 25, then the voltage rise across the integrator 16, i.e. (o) pass by

OA | Az curve. But due to the second and third modulation types (amplitude and latitude), the voltage increase on integrator 16 occurs along direct OA | Ar, i.e. at the beginning of the period, the input pulses U have a small amplitude and duration of UHUH and gshc and, when summed, do not give a bulge that is characteristic of the exponent OA | A3. From the output of the integrator 16, the voltage is supplied to an actuator with an electric actuator 17, the movements of which exactly reproduce the form of the control signal. This is achieved by a combined control method. So, if only one type of modulation (frequency) was used, then the motions would be characterized by non-linear distortions. Distortions are strongest at high pulse frequency, since in this region (1-2) the exponent starts to noticeably bend. But due to the fact that at this time the amplitude and duration of the input signal Uex rises to UHaK and, "", the voltage continues to rise and the movements of the actuator with electric actuator 17 will go straight. At low frequencies, on the contrary, the amplitude of the input signal of the source signal is less than the average amplitude Uv. Therefore, the initial portion is not characterized by such a high voltage. As a result, the shape of the control signal will be reproduced without distortion, and the movements will occur with a maximum span.

The effect of using the motor unit control device is that, thanks to its use as a control signal, with a triple type of modulation — amplitude-frequency-latitude, it was possible to expand the dynamic range of the motor unit, making the range of motion of individual limb links larger with the shape control signal. By covering the pulse amplifier 13 with negative feedback in the form of a second-order link 14, the speed of the control device is improved by reducing the time constant of the system. This increases the speed of motion control. In addition, the pulse amplifier 13, covered by negative feedback with the second-order link 14, is a boost dynamic phase-generating link, which is the antipode of the phase-proportional link of the integrator 16. This compensates for the delay of the phase and the control signal is received to an actuator with electric actuator 17 without phase delay. This achieves the execution of movements synchronously with the control signal. Due to the triple type of modulation, the noise immunity of the entire control device is greatly increased, since the total noise immunity is equal to the product of the noise immunity of individual modulation types.

Thus, the described control device of the motor apparatus has high noise immunity, high speed, minimal non-linear distortion with a large amplitude swing of motion and allows movement to occur synchronously with the control signal without phase lag. The control device of the motor apparatus is as close as possible to the mechanisms of control in living nature. In particular, the movement of the foot is controlled by the regulatory apparatus of the spinal cord, which is based on the mechanism of presynaptic inhibition - the most effective form of inhibition in the spinal cord.

0 central nervous system. When the sensory receptors of the foot are activated, the spinal cord receives triple-modulated impulses: in amplitude, in frequency and in duration. These

5 impulses activate the presynaptic inhibition mechanism, which directs the control signal to the foot along the centrifugal nerve. The nerve is a proportionally integrating link. Such a control system has a high speed, increased noise immunity and allows to perform coordinated movements with great accuracy.

The proposed system can be used to control the flexion of the foot when designing an artificial foot.

5 walking devices.

Claims (1)

Invention Formula Motor control unit 0 apparatus comprising a sensor, an actuator with an electric drive, two amplifiers integrating the circuit and a power amplifier, characterized in that, in order to increase the accuracy of controlling the coordinated movements of the apparatus, into it 5, three standby multivibrators, two emitter repeaters, a sawtooth generator, differentiating a chain with limiters, a second-order link and an integrator, the sensor, the first waiting multivibrator, the first differentiating circuit with a limiter, the second waiting multivibrator, the first emitter, the first repeater, sawtooth generator, third standby multivibrator, first amplifier, second differential circuit with limiter, integrator, pulse amplifier, power amplifier, integrate op and actuator electrically connected in series, and the generator output a sawtooth voltage is further connected to a second amplifier which, via a second emitter follower is connected with L Bg FIG. 2 the first amplifier, and the output of the pulse amplifier through the link of the second order is connected to the input of the pulse amplifier. S 13 20 .21, 21 / 23 27 ./ 28 29 thebes